Help! I can't find stashed items

[HusMusen]

I put a bunch of items in the stash but I don't know where to find them and now I can't progress

[Seni]

you find them at the mail posts in game!

[HusMusen]

Where can I find the mail posts? i looked but I can't find them

[Elliot]

I also can't find the mailposts!

[DezuCchi]

One of the main mailpost I always go to is the one in Bandle University Root Market!! You follow the ramp up next to the backpack area where Penelope and Jasper are and there will be a cute lil crab with a top hat there if you have stashed items :)

[Orange]

There's only two mailposts in the whole game.

One next to Frankle in Yarnville.
One at the elevator to the Unity Tree in Bandle University Root Market.